1. Field of the Invention
This invention generally relates to electric apparatus for toasting food, and more specifically to a toaster that overcomes many of the problems of current toasters.
2. Description of Related Art
Toasters have existed for many years and often embody a basic construction in which a housing essentially surrounds the toasting mechanism. Elongated openings through the top of the housing provide access to internal basket assemblies. The basket assemblies typically support the bread slices or the like so their outer surfaces are essentially parallel to and proximate heater plates within the toaster. An consumer manipulates a slider or other control that establishes a time interval for toasting the bread slices. After the bread slices are placed into the basket assemblies, the consumer depresses a mechanical lever or performs some similar function. The basket assemblies move to a latched lower position compressing one or more return springs. This energizes heating elements on each side of the bread slice. A bimetallic switch or similar device, being adjustable by the above-mentioned button or slider, releases the latch after the toasted bread slice has reached the desired level of darkness. The compressed springs elevate the basket assemblies and the toasted bread slices so the consumer can grasp the top portion of the slice. Toasters with this basic construction have been popular for a number of years.
However, removal of toast from conventional toasters is not always easy. Small toast slices are a particular problem if, after toasting, they lie below the top. If one reaches inside through the elongated opening to retrieve such a toast slice, there is a risk of burning a finger on adjacent hot surfaces. Using a utensil, such as a fork, is likely to damage the heating elements. If an consumer tries to remove a food slice from a basket assembly while the heaters are energized, there is a danger of electric shock and even electrocution.
Often these toasters do not toast food slices uniformly, as evidenced by varying shades that often appear across the food slice surface. The top portion of the food slice is usually darker and drier than the bottom portion due to its exposure to rising hot air. Such toasters are also inefficient. Infrared radiation is the primary toasting property. However, the heating elements radiate a certain percentage of their energy into the room through the elongated openings through the top. There is also a loss of heat through the slots due to convection. As a result considerable energy is wasted, which lowers the overall operating efficiency for the toaster.
More recently it has become desirable for toasters to receive other foodstuffs, like bagels, flatbread, Panini sandwiches and the like. In the following discussion the phrase “food slice” is intended to designate all such foodstuffs as might be inserted into a toaster. In U.S. Pat. No. 7,189,945 (2007) to Starr et al. a toaster includes a chassis that defines a cavity with spaced, parallel heating elements. The chassis has a door that closes an open end. When the door opens, in one embodiment, it pulls a carriage with food slice basket assemblies from the cavity and chassis. An consumer loads food slices in the basket assemblies and then closes the door. When the door closes, the heating elements are energized to toast the food slices. In one proposed embodiment, the toaster includes a motor to facilitate the opening and closing of the door.
The Starr et al. patent states that the disclosed apparatus provides even toasting of a variety of food slices by controlling the loss of heat and moisture from the enclosed heating chamber. However, it also appears each of the embodiments include structures that increase manufacturing costs and introduce potential reliability issues. For example, in the first and third embodiments the use of sliding doors and a sliding carriage requires the assembly of a large number of components which add to manufacturing costs. A sliding carriage also acts as a crumb tray, but during operation crumbs may slide off the tray and jam the carriage.
An consumer of each of any one of the first, second and third embodiments will probably close the door against the force of a door-opening spring. The consumer must block the back of the toaster either by abutting it against a vertical surface or by grasping the back edge or cover with one hand. Otherwise it is likely that the toaster will slide along a countertop or other supporting surface. After repeated toasting cycles heat may build up at the top back corner of the toaster. Consequently, the toaster must include structures that assure this buildup does not produce a potential for burning the consumer's hand that grasps the top back corner. In addition, this required action for manual operation differs from the one-handed action used for conventional toasters; this may make the toaster less desirable to use. A suggested alternative is to provide a motor drive to operate the door, but this also increase expense and the potential for reliability problems.
Many consumers want to store their toasters on counter tops characterized by limited counter space. Prior art toasters often require significantly more counter space than the space associated with food slices being toasted and the heating elements. Consequently, toasters are stored in cabinets or the like that are not as convenient as a countertop.
What is needed is a toaster that is compact, has low manufacturing costs, controls heat and moisture loss for uniform toasting, is easy to use and is reliable. Such a toaster should deliver the finished toast at a position that minimizes the potential for injury by inadvertent contact with heating elements or any other hot surfaces. Finally, the toaster should operate with minimal energy requirements.